Package org.apache.cassandra.db.commitlog

Class CommitLogSegment

java.lang.Object
org.apache.cassandra.db.commitlog.CommitLogSegment
Direct Known Subclasses:
DirectIOSegment, FileDirectSegment, MemoryMappedSegment
public abstract class CommitLogSegment extends Object

  • Field Details

  • Method Details

    • additionalHeaderParameters

      protected Map<String,String> additionalHeaderParameters()
      Provide any additional header data that should be stored in the CommitLogDescriptor.

    • createBuffer

      protected ByteBuffer createBuffer()

    • resetReplayLimit

      public static void resetReplayLimit()
      FOR TESTING PURPOSES.

    • writeCDCIndexFile

      public static void writeCDCIndexFile(CommitLogDescriptor desc, int offset, boolean complete)
      We persist the offset of the last data synced to disk so clients can parse only durable data if they choose. Data in shared / memory-mapped buffers reflects un-synced data so we need an external sentinel for clients to read to determine actual durable data persisted.

    • writeSyncMarker

      protected static void writeSyncMarker(long id, ByteBuffer buffer, int offset, int filePos, int nextMarker)
      Create a sync marker to delineate sections of the commit log, typically created on each sync of the file. The sync marker consists of a file pointer to where the next sync marker should be (effectively declaring the length of this section), as well as a CRC value.
      Parameters:
      buffer - buffer in which to write out the sync marker.
      offset - Offset into the buffer at which to write the sync marker.
      filePos - The current position in the target file where the sync marker will be written (most likely different from the buffer position).
      nextMarker - The file position of where the next sync marker should be.

    • isStillAllocating

      public boolean isStillAllocating()

    • getCurrentCommitLogPosition

      public CommitLogPosition getCurrentCommitLogPosition()
      Returns:
      the current CommitLogPosition for this log segment

    • getPath

      public String getPath()
      Returns:
      the file path to this segment

    • getName

      public String getName()
      Returns:
      the file name of this segment

    • getCDCFile

      public File getCDCFile()
      Returns:
      a File object representing the CDC directory and this file name for hard-linking

    • getCDCIndexFile

      public File getCDCIndexFile()
      Returns:
      a File object representing the CDC Index file holding the offset and completion status of this segment

    • internalClose

      protected void internalClose()
      Close the segment file. Do not call from outside this class, use syncAndClose() instead.

    • coverInMap

      public static <K> void coverInMap(ConcurrentMap<K,IntegerInterval> map, K key, int value)

    • markClean

      public void markClean(TableId tableId, CommitLogPosition startPosition, CommitLogPosition endPosition)
      Marks the ColumnFamily specified by id as clean for this log segment. If the given context argument is contained in this file, it will only mark the CF as clean if no newer writes have taken place.
      Parameters:
      tableId - the table that is now clean
      startPosition - the start of the range that is clean
      endPosition - the end of the range that is clean

    • getDirtyTableIds

      public Collection<TableId> getDirtyTableIds()
      Returns:
      a collection of dirty CFIDs for this segment file.

    • isUnused

      public boolean isUnused()
      Returns:
      true if this segment is unused and safe to recycle or delete

    • contains

      public boolean contains(CommitLogPosition context)
      Check to see if a certain CommitLogPosition is contained by this segment file.
      Parameters:
      context - the commit log segment position to be checked
      Returns:
      true if the commit log segment position is contained by this segment file.

    • dirtyString

      public String dirtyString()

    • onDiskSize

      public abstract long onDiskSize()

    • contentSize

      public long contentSize()

    • toString

      public String toString()
      Overrides:
      toString in class Object

    • getCDCState

      public CommitLogSegment.CDCState getCDCState()

    • setCDCState

      public CommitLogSegment.CDCState setCDCState(CommitLogSegment.CDCState newState)
      Change the current cdcState on this CommitLogSegment. There are some restrictions on state transitions and this method is idempotent.
      Returns:
      the old cdc state